I. Field of the Invention
This invention relates to the thermoregulatory nature of articles of clothing.
One function of clothing is to provide humans with a means of maintaining body temperature between limits which are both comfortable and necessary for normal body function.
The human body possesses a tissue known as adipose tissue or fat, of which there are two recognized types; `Yellow or White Fat` and `Brown Fat`. Each characterized by; structure, localization, vascularisation and function of the cells.
White fat has a great capacity to insulate the body from heat loss, thereby assisting temperature regulation. White fat cells are found over the entire human body, the general anatomical distribution of which is characteristic to humans.
Brown fat is a tissue capable of metabolism which actively generates heat, thereby assisting temperature regulation. Brown fat cells are found in localized areas over the human body, the general anatomical distribution of which is characteristic of humans.
It is recognized that active brown fat possesses the ability to generate heat in response to cold stress, and of all tissues it is believed to have the greatest capacity for heat production.
Relatively high densities of brown fat cells, and relatively high densities of white fat cells (the latter being hereinafter defined as `fat pads`) are located over the body; Where these coincide the white fat cells are theoretically providing insulation/lagging for any increased cellular heat production in this area.
As well as generating heat, and insulating in order to conserve increased internal heat produced, the body also controls temperature (hereinafter defined as `thermoregulates`) by redistribution of blood flow to the skin's surface; decreasing this flow to insulate or build up internal heat, and increasing this flow to cool down. Sweating may also occur if the body's requirements for heat loss are even greater.
Certain specific areas of the skin (hereinafter defined as areas `over the body`) appear to be particularly sensitive to their (immediate) environmental climate (hereinafter defined as `microclimate`), and in particular the temperature of the microclimate. In the case of a clothed human being, the environment between the skin and the clothing would be the microclimate. Specific areas of the body which are particularly sensitive to their microclimate are hereinafter defined as `temperature sensitive sites`.
The skin is covered with millions of tiny temperature sensors, which tell the body how hot or cold it is outside. Messages are then passed from the sensors to the main control center, (the hypothalamus) located in the brain, which will in turn direct the body either to force up its internal heat generation (hereinafter defined as `metabolism`), increasing the conversion of the body's fuel into heat, thereby increasing its temperature, if it is cold, or drive down its metabolism and temperature, if it is hot.
It matters little that there might be ice and snow outside as the microclimate between the skin and clothing may well be warm or even hot, and it is this microclimate which will affect the temperature sensors and not the cold conditions outside.
The spine is the brain's chief temperature sensor, and therefore, the brain will tend to follow the messages sent from the spine's temperature sensors, above those from other areas of the skin.
So, if the microclimate of the spine is cool, the nerves are stimulated in this region, sending messages to the brain to increase metabolism. This means that everything including the immune system, will be working harder.
If, however, the microclimate of the spine is either
(i) too warm, resulting in a lack of nerve stimulation, or PA1 (ii) too hot; resulting in heated nervous stimulation, which continues to stimulate metabolism but maintains an increasingly hot microclimate, PA1 (a) Warmth; this may encourage the use of fabrics which efficiently trap air, such as fleece, pile, wool, or, in nylon wetsuit type garments, which efficiently trap a layer of water. These garments do not provide for an exchange of temperature (hereinafter defined as `heat exchange`) by having a low insulatory capacity specifically in temperature sensitive sites. PA1 (b) Durability; here tough fibres such as tightly woven mesh or solid materials which are abrasion resistant and puncture-proof, are used to provide lasting quality with continued use. Such garments are generally heavy and/or bulky in construction. PA1 (c) Protection; special fabrics which are heat and/or chemical and/or water resistant or proof, for example, for dealing with industrial waste (eg radiation or poisons) or `storm suits` for use in extreme weather conditions. These garments are generally uncomfortable to wear. PA1 (d) Breathability; to provide for heat loss and comfort either by having a ventilatory capacity to exchange air or moisture between the microclimate and the external climate (hereinafter defined as `vapour exchange`). This is in contrast to common current designs wherein the fabric absorbs sweat from the skin surface before finally evaporating from the surface of the fabric, with the result that the skin is inefficiently cooled on account of a latent cooling of the fabric rather than the skin. PA1 1. Providing increased heat exchange by means of reduced insulation (herein defined as `lower insulatory capacity`) of temperature sensitive sites--reducing insulation of temperature sensitive areas not protected by `fat pads` --allowing for improved response to increase metabolism as required, and improved heat exchange by, for example, conduction and radiation to and from the surface of the skin, and/or PA1 2. Providing for increased vapour exchange by means of specific ventilation of temperature sensitive areas (herein defined as `increased ventilatory capacity`)--allowing flexibility for rapid increases in heat generation owing to facility for improved vapour exchange eg the loss of excess heated air or humidity, by, for example, convection and evaporation of sweat from the surface of the skin. PA1 (a) `sector`--any shape having a continuous perimeter located within the garment eg a hole in each armpit site (as hereinafter defined), or a hole in the spinal cord site (as hereinafter defined). PA1 (1) spine--extends along the center of the back covering the entire length and breadth of a chain of 29 vertebrae, from the uppermost vertebra (C1) in the center base of the skull to the lowermost vertebra (S4) in the central lower portion of the hips. Beginning with the uppermost vertebra and working downwards, the groups of vertebrae are as follows; the cervical or `neck` vertebrae (C1-C7 inclusive), the thoracic or `back` vertebrae (T1-T12 inclusive), the lumbar or `small of the back` vertebrae (L1-LS inclusive) and, finally, the sacral or `lower end of the hips` vertebrae (S1-S5 inclusive) (hereinafter defined as the `spinal cord site`). (The lowermost portion of the spine itself is the coccygeal section of vertebrae (C1-C4 inclusive). PA1 (2) front and back of the neck--where there is a relative absence of fat pads, and which is characterized by a relatively higher concentration of nervous tissue close to the skin surface, is hereinafter defined as the `front and back of neck site`; PA1 (3) back of the knees--hereinafter defined as the `back of knee site`; PA1 (4) front of the chest--where there is a relative absence of fat pads, and where there is a relatively higher concentration of nervous tissue close to the skin surface, is hereinafter defined as the `front of chest site`; PA1 (5) below the breasts--this area located just below the breasts and not protected by fat pads, is hereinafter defined as `the breast site`; PA1 (6) the armpits--areas not protected by fat pads, which sweat relatively more, and which have relatively higher concentrations of lymph glands close to the skin surface, are hereinafter defined as `the armpit sites`; PA1 (7) front of elbows--hereinafter defined as `front of elbow site`; PA1 (8) groin--area not protected by fat pads, which sweats relatively more, and which has reproductive tissues and/or organs and relatively higher concentrations of lymph glands close to the skin surface, is hereinafter defined as the `groin site`; PA1 (9) knee and shins--areas not protected by fat pads hereinafter defined as `shin sites`. PA1 (10) `sacrum dimples` --located at the top of the sacrum region hereinafter defined as the `sacrum dimples site`. PA1 cut-away sleeve cut-off top, cut-away sleeve, sleeveless, short sleeve, sleeve with collar, long sleeve, long sleeve with collar, long sleeve with hood; PA1 sweatshirt, shirt, polo shirt, vest top, jacket, brassiere. PA1 cut-away shorts, shorts, mid-length trousers, long trousers; PA1 cycling shorts, underpants, jogging pants, jeans, trews. PA1 swimming costume, jump suit, flying suit, leotard, boiler suit. PA1 (1) in at least a substantial area of its uppermost region (`uppermost region` is herein defined as vertebrae C1-T12 inclusive) including at least the whole of the uppermost section or portion of this region, is of relatively lower insulatory capacity and/or of relatively higher ventilatory capacity; and PA1 (2) in at least a substantial area of its lowermost region (`lowermost region` is herein defined as vertebrae L1-S5 inclusive) including at least the whole of the lowermost section or portion of this region, is of relatively lower insulatory capacity and/or of relatively higher ventilatory capacity. PA1 (1) at least a substantial area of the uppermost region of the sector(s) including at least the whole of the uppermost section or portion of this region. and PA1 (2) at least a substantial area of the lowermost region of the sector(s) including at least the whole of the lowermost section or portion of this region.
either of which might be the case if the clothing over the spine provides too much insulation or too little ventilation, then the spine overheats.
In the overheated state the spine will direct the brain in (i) above to develop a sluggish metabolism (including suppressed nervous activity and a sluggish immune system), the net result being less fuel-to-heat conversion and lowered heat output either in local areas of the body or in the body overall, with the potential risk of cellular damage due to low temperature and/or low blood flow, and, in (ii) above the nervous tissue of the spine, owing to excess temperature and/or blood flow in excess of requirements, may suffer cellular heat damage and/or fusing, much in the same manner as an overheated electrical wire.
A similar situation may also arise in other temperature sensitive sites. Such a situation is hereinafter defined as `overheating`.
Indeed, the spine, being the brain's chief temperature sensor, appears to function in much the same way as a thermostat, and within the scope of this invention, is regarded as the key temperature sensitive region of the body.
The conclusion is that it is desirable to have clothing having sectors which specifically prevent the spine from overheating. Furthermore, it is one desirable object to provide clothing with at least a sector occupying substantially and substantially exclusively (as hereinafter defined) the spinal cord site (as hereinafter defined), where convenient to the garment construction.
The anatomical distribution of the body's natural clothing of muscle and/or bulky fatty tissue is characteristic to humans.
A second category of temperature sensitive sites are those which when a human being observes their naked body in a mirror, whether fat, thin, short or tall, it is noticeable how certain areas are seen to be padded with much less muscle and/or bulky fatty tissue than other areas. These areas not protected by fat pads include the spine, back of neck, back of knees, front of chest, below the breasts, the sacral dimples (hereinafter defined), armpits, front of elbows and groin and shins.
The general relative absence of fat pads in these areas appears to suggest that their insulatory requirements are less than for those areas which are generally relatively more protected/insulated by fat pads.
The conclusion is that it is desirable to have clothing that keeps the body warm and/or insulated whilst having sectors which are specifically less insulated in areas of relatively less fat pads.
A third category of temperature sensitive sites are those which tend to sweat more than other areas of the body. They can be observed by looking at the sweat pattern on the shirt of an athlete after a hard `work-out`, and they include the spine and all of the other areas not protected by fat pads.
Sweating is a major way in which the human body is able to lose heat to keep cool (in a warm or hot microclimate), by the latent heat of evaporation of sweat from the skin surface, and so control its temperature and metabolism.
The body is constantly raising its activity level and temperature in response to the germs and diseases which are attacking it 24 hours a day. Unless the skin can thermoregulate freely, the body will not be able to maintain the requisite temperature and activity level, and so the body may become infected and/or suffer cellular damage and/or DNA damage, which is likely to be inefficiently repaired.
The fact that the skin is characterized by areas which apparently sweat more than others would suggest their need to be able to lose heat and sweat properly in order to thermoregulate efficiently, specifically in order to maintain their temperature between those limits which are necessary for their functional demands at any particular time.
It is concluded that improved cellular activity of the body would be provided by clothing having sectors specifically in sweaty regions, thereby allowing the body to sweat effectively.
Indeed, it would appear to be a very important consideration that in these `sweaty` areas can be found relatively higher concentrations of lymph glands (for temperature sensitive immune cell production) and/or lymph and/or nervous tissue (temperature sensitive tissue) and/or large blood vessels close to the surface of the skin. In particular the spine, back of the neck, front of the chest, armpits and groin.
The location of these glands and nervous tissue being close to the skin's surface, appears to suggest that these temperature sensitive sites need to be able to control their temperature between narrow limits and/or lose heat and sweat properly, in order to maintain their temperature between those limits which are necessary for their normal and/or optimum functioning.
Indeed, in the case of a person who is ill, it can be observed that lymph glands often swell up and come to the surface, where, (provided their microclimate allows) they will be better able to readily increase their metabolism (in an unsuppressed manner), to keep cool, and control their temperature, ie avoid overheating.
It is concluded that it is desirable to have clothing which incorporates sectors which provide for efficient thermoregulation, specifically in sites of high densities of lymph glands.
A particularly `sweaty` area is the groin site, where reproductive glands are located close to the surface of the skin, where, provided their microclimate permits, they will be able to lose heat and sweat properly, in order to maintain, over 24 hours, their temperature between those limits which are necessary for their normal and/or optimum functioning. Indeed, the testicles (temperature sensitive sites of reproductive cell production), since they hang outside the body, are perfectly positioned to do this.
It is concluded that improved reproductive cell activity would be encouraged by clothing having specific sectors that allow reproductive tissues/organs to thermoregulate efficiently.
Current/conventional clothing (which is largely fashion orientated) does not provide for the thermoregulatory needs of the aforementioned temperature sensitive sites. As a result, those areas which are relatively less protected by `fat pads`, and which would therefore appear to require relatively less insulation than surrounding areas, may be defined as `overinsulated`, and may well overheat as a result, (causing all kinds of strain and/or problems for the body).
Furthermore, when overinsulated the aforementioned `sweaty` areas, which need to be able to sweat easily, including those areas with glands and/or nervous tissue close to the skin's surface so that they can thermoregulate properly, may be prevented from doing so. In such an overheated microclimate these temperature sensitive sites may not have the flexibility to respond quickly enough to control their temperature, as appropriate, between those limits which are necessary for their normal and/or optimum functioning.
It is concluded that it is desirable to have sectors within clothing providing less insulation and/or more ventilation (as appropriate) in temperature sensitive sites, and furthermore, that such clothing will keep the body warmer by stimulating and raising metabolism, and allow rapid unsuppressed increases in metabolism, as required, either in local regions of the body or throughout the entire body, according to the demands placed upon the body.
II. Description of the Prior Art
Protective clothing, designed primarily for use in extreme climatic and other extreme and/or hazardous conditions, eg fire, radiation, seems to have little regard for the body's thermoregulatory requirements. This might normally be done by using ventilated fabrics, such as string vest or mesh material, and/or microporous waterproof fabrics eg laminated or coated fabrics, to aid loss of heat from body and evaporation of sweat. An example of such clothing might be climbing wear made from a microporous waterproof fabric.
In a sense all clothing may be described as protective, in that it provides the body with assistance against the elements.
However current protective clothing does not have regard to the thermoregulatory needs of the temperature sensitive sites, as distinct from surrounding areas. As a result of this non-discriminatory factor, both insulation and ventilation tend to be applied and/or provided uniformly over the entirety of the surface of the skin being protected by the garment, and not in accordance with the body's thermoregulatory requirements, which appear to require non-uniform ventilation and insulation over the body surface.
Furthermore, a common problem with such clothing is optimising a balance between various factors and/or functional requirements:
In optimising such a balance, one or more of these factors/functions may well be compromised. This may well result for example in a heavy, durable and uncomfortable, protective, bulky, but warm garment with overall but minimal breathability. Such a garment would result in an overall reduction of the body's ability to generate and/or lose heat and sweat efficiently and effectively, thereby putting the body's temperature sensitive sites under a great strain in direct proportion to the stresses exerted on the body whilst wearing such clothing.